Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 101059
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0459 MDT Wednesday, September 10, 2014

This forecast is for Wednesday, September 10, 2014:

If the trigger temperature of 57.5 F/14.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 165 ft/min (0.8 m/s)
   Maximum height of thermals.................. 13660 ft MSL (6902 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11106 ft MSL (4348 ft AGL)
Thermal soaring outlook for Thursday 09/11..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18295 ft MSL (11537 ft AGL)
Wave soaring outlook for Thursday 09/11........ Fair

Remarks...

Sunrise/Sunset.................... 06:35:55 / 19:16:42 MDT
Total possible sunshine........... 12 hr 40 min 46 sec (760 min 46 sec)
Altitude of sun at 12:55:50 MDT... 55.80 degrees

Upper air data from numerical model forecast valid on 09/10/2014 at 0600 MDT

Freezing level.................. 12588 ft MSL (5830 ft AGL)
Convective condensation level... 9742 ft MSL (2984 ft AGL)
Lifted condensation level....... 11367 ft MSL (4609 ft AGL)
Lifted index.................... -2.3
K index......................... +24.7

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -65.6 -86.1   255   56   29   3.2   1.7      M     M       M      M    M
 45000  -59.1 -74.4   255   82   42   7.5   4.1      M     M       M      M    M
 40000  -47.4 -53.3   250   91   47   7.0   3.8      M     M       M      M    M
 38000  -43.3 -45.9   250   93   48   7.0   3.8      M     M       M      M    M
 36000  -39.1 -38.4   250   96   49   7.0   3.8      M     M       M      M    M
 34000  -35.3 -31.5   250   94   48   6.0   3.3      M     M       M      M    M
 32000  -31.7 -25.1   250   90   46   6.0   3.3      M     M       M      M    M
 30000  -28.9 -20.0   250   82   42   3.8   2.1   43.3 109.9    19.7      M    M
 29000  -27.8 -18.0   250   77   40   3.8   2.1   41.0 105.7    18.1      M    M
 28000  -26.6 -15.9   250   72   37   3.8   2.1   38.8 101.8    16.6      M    M
 27000  -25.3 -13.5   255   65   33   3.7   2.1   35.9  96.7    14.6      M    M
 26000  -24.1 -11.4   255   59   30   3.8   2.1   33.7  92.6    12.9      M    M
 25000  -23.0  -9.4   260   53   27   3.9   2.1   31.5  88.7    11.3      M    M
 24000  -21.4  -6.5   265   48   25   6.9   3.8   30.0  85.9    10.1      M    M
 23000  -19.3  -2.7   265   44   23   7.1   3.9   28.9  84.1     9.3      M    M
 22000  -17.3   0.9   265   40   21   7.2   4.0   28.1  82.6     8.6      M    M
 21000  -15.2   4.6   265   37   19   7.2   3.9   27.2  80.9     7.9      M    M
 20000  -13.1   8.4   265   34   18   7.3   4.0   26.3  79.3     7.1      M    M
 19500  -12.1  10.2   265   33   17   7.3   4.0   25.9  78.6     6.7      M    M
 19000  -11.1  12.0   265   31   16   6.9   3.8   25.5  77.9     6.3      M    M
 18500  -10.3  13.5   265   28   15   5.1   2.8   24.8  76.6     5.7      M    M
 18000   -9.5  14.9   265   25   13   5.1   2.8   24.0  75.3     5.1      M    M
 17500   -8.6  16.5   270   23   12   6.9   3.8   23.4  74.1     4.5      M    M
 17000   -7.6  18.3   275   22   11   7.2   3.9   22.9  73.3     4.1      M    M
 16500   -6.5  20.3   280   21   11   6.8   3.7   22.5  72.6     3.7      M    M
 16000   -5.7  21.7   280   20   10   6.0   3.3   21.9  71.5     3.2      M    M
 15500   -4.8  23.4   285   19   10   6.0   3.3   21.3  70.4     2.6      M    M
 15000   -3.9  25.0   290   17    9   5.9   3.2   20.7  69.3     2.0      M    M
 14500   -3.1  26.4   290   16    8   6.0   3.3   20.1  68.1     1.4      M    M
 14000   -2.3  27.9   295   15    8   4.8   2.6   19.4  66.9     0.8      M    M
 13500   -1.3  29.7   305   15    8   4.6   2.5   18.2  64.7    -0.5    546  2.8
 13000   -0.5  31.1   310   15    8   6.2   3.4   17.5  63.5    -1.1    508  2.6
 12500    0.3  32.5   315   15    8   5.1   2.8   16.9  62.5    -1.7    467  2.4
 12000    1.2  34.2   320   15    8   8.2   4.5   16.4  61.5    -2.3    426  2.2
 11750    1.7  35.1   320   15    8   7.5   4.1   16.2  61.2    -2.5    403  2.0
 11500    2.3  36.1   325   15    8   8.1   4.5   16.1  60.9    -2.7    379  1.9
 11250    2.8  37.0   325   15    8   6.6   3.6   15.9  60.6    -2.9    356  1.8
 11000    3.2  37.8   330   14    7   5.4   3.0   15.6  60.0    -3.3    337  1.7
 10750    3.6  38.5   330   14    7   6.1   3.3   15.3  59.5    -3.6    317  1.6
 10500    4.0  39.2   335   13    7   6.0   3.3   15.0  59.0    -3.9    297  1.5
 10250    4.5  40.1   340   13    7   5.5   3.0   14.7  58.5    -4.2    277  1.4
 10000    4.8  40.6   345   13    7   5.3   2.9   14.4  57.8    -4.6    259  1.3
  9750    5.2  41.4   345   13    7   5.8   3.2   14.0  57.3    -4.9    240  1.2
  9500    5.6  42.1   350   13    7   5.8   3.2   13.7  56.7    -5.3    220  1.1
  9250    6.0  42.8   355   13    7   6.1   3.3   13.4  56.2    -5.6    201  1.0
  9000    6.5  43.7   355   14    7   6.4   3.5   13.2  55.7    -5.9    180  0.9
  8750    6.9  44.4   355   15    8   7.5   4.1   12.9  55.3    -6.2    158  0.8
  8500    7.5  45.5   350   15    8   8.3   4.6   12.8  55.1    -6.3    134  0.7
  8250    8.1  46.6   350   15    8   8.1   4.5   12.7  54.9    -6.5    109  0.6
  8000    8.7  47.7   345   14    7   7.9   4.3   12.6  54.6    -6.7     85  0.4
  7750    9.2  48.6   345   13    7   8.9   4.9   12.5  54.4    -6.8     60  0.3
  7500    9.8  49.6   345   12    6   7.5   4.1   12.4  54.3    -7.0     34  0.2
  7250   10.2  50.4   345   10    5   4.5   2.4   12.4  54.4    -6.9     15  0.1
  7000   10.6  51.1   345    9    4   5.5   3.0   12.5  54.5    -6.9      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           09/10/2014 at 0900 MDT          |       09/10/2014 at 1200 MDT
                                           |
K index... +23.0  LI... -1.4               | K index... +16.8  LI... -1.9
CAPE... +186.8  CIN... M                   | CAPE... +282.6  CIN... -1.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.8 -84.6  255  62 32   2.4   1.3 | -64.6 -84.3  255  68 35   2.3   1.2
 45000 -59.2 -74.6  250  87 45   7.4   4.0 | -59.3 -74.7  255  91 47   6.9   3.8
 40000 -48.1 -54.6  250  94 48   7.1   3.9 | -49.0 -56.2  250  91 47   6.6   3.6
 38000 -43.8 -46.8  250  93 48   7.1   3.9 | -45.0 -49.0  250  85 44   6.6   3.6
 36000 -39.5 -39.1  250  91 47   7.2   3.9 | -41.0 -41.8  250  78 40   6.6   3.6
 34000 -35.5 -31.9  250  86 44   5.4   3.0 | -37.5 -35.5  255  70 36   5.3   2.9
 32000 -32.2 -26.0  250  79 41   5.4   3.0 | -34.0 -29.2  260  60 31   5.3   2.9
 30000 -29.9 -21.8  255  69 36   3.0   1.7 | -31.1 -24.0  265  51 26   4.4   2.4
 29000 -29.0 -20.2  255  63 33   3.0   1.7 | -29.8 -21.6  270  46 24   4.4   2.4
 28000 -28.0 -18.4  260  57 30   3.0   1.6 | -28.5 -19.3  275  42 21   4.4   2.4
 27000 -26.9 -16.4  265  51 26   4.2   2.3 | -27.1 -16.8  280  38 20   4.6   2.5
 26000 -25.7 -14.3  265  45 23   4.2   2.3 | -25.8 -14.4  280  35 18   4.6   2.5
 25000 -24.4 -11.9  270  39 20   4.4   2.4 | -24.4 -11.9  280  32 17   4.7   2.6
 24000 -22.7  -8.9  275  35 18   7.7   4.2 | -22.6  -8.7  280  30 16   7.4   4.1
 23000 -20.4  -4.7  275  34 17   7.7   4.2 | -20.4  -4.7  285  29 15   7.5   4.1
 22000 -18.1  -0.6  275  32 16   7.7   4.2 | -18.1  -0.6  285  29 15   7.6   4.2
 21000 -16.0   3.2  275  30 15   6.7   3.7 | -16.0   3.2  285  28 14   7.2   3.9
 20000 -14.1   6.6  275  28 14   6.8   3.7 | -13.8   7.2  290  27 14   7.2   3.9
 19500 -13.1   8.4  275  27 14   6.8   3.8 | -12.8   9.0  295  27 14   7.2   3.9
 19000 -12.2  10.0  270  26 13   6.9   3.8 | -11.7  10.9  295  27 14   6.8   3.7
 18500 -11.2  11.8  275  24 12   6.8   3.7 | -10.8  12.6  295  26 13   5.9   3.2
 18000 -10.2  13.6  275  22 11   6.9   3.8 | -10.0  14.0  295  25 13   5.9   3.2
 17500  -9.3  15.3  280  20 10   6.4   3.5 |  -9.1  15.6  295  25 13   5.9   3.3
 17000  -8.3  17.1  285  18  9   6.3   3.5 |  -8.2  17.2  295  23 12   6.0   3.3
 16500  -7.0  19.4  295  17  9   6.1   3.4 |  -7.4  18.7  295  22 11   6.2   3.4
 16000  -6.1  21.0  300  17  9   6.1   3.3 |  -6.4  20.5  295  21 11   6.6   3.6
 15500  -5.2  22.6  305  17  9   5.9   3.2 |  -5.0  23.0  300  20 10   6.9   3.8
 15000  -4.3  24.3  310  18  9   5.7   3.1 |  -4.0  24.8  305  20 10   7.1   3.9
 14500  -3.5  25.7  315  19 10   5.7   3.1 |  -2.9  26.8  310  20 10   7.1   3.9
 14000  -2.6  27.3  315  19 10   5.8   3.2 |  -1.9  28.6  315  20 10   7.1   3.9
 13500  -1.8  28.8  320  20 10   5.8   3.2 |  -0.8  30.6  320  21 11   7.2   3.9
 13000  -0.9  30.4  315  20 10   6.3   3.4 |   0.2  32.4  320  20 10   7.4   4.0
 12500   0.0  32.0  315  18  9   6.3   3.5 |   1.3  34.3  320  20 10   7.1   3.9
 12000   0.9  33.6  315  17  9   5.4   3.0 |   2.3  36.1  320  19 10   7.1   3.9
 11750   1.3  34.3  315  16  8   5.7   3.1 |   2.8  37.0  320  18  9   7.1   3.9
 11500   1.7  35.1  310  15  8   5.2   2.9 |   3.3  37.9  320  17  9   7.0   3.8
 11250   2.1  35.8  310  14  7   7.3   4.0 |   3.7  38.7  315  17  9   6.3   3.5
 11000   2.6  36.7  315  14  7   7.5   4.1 |   4.2  39.6  315  16  8   6.5   3.6
 10750   3.1  37.6  315  13  7   5.7   3.1 |   4.6  40.3  310  14  7   7.0   3.9
 10500   3.5  38.3  315  12  6   6.3   3.5 |   5.1  41.2  305  13  7   7.0   3.8
 10250   3.9  39.0  315  11  6   5.3   2.9 |   5.5  41.9  300  11  6   4.7   2.6
 10000   4.3  39.7  320  11  6   5.1   2.8 |   5.8  42.4  295   9  5   5.8   3.2
  9750   4.6  40.3  330  10  5   6.0   3.3 |   6.3  43.3  285   7  3   9.3   5.1
  9500   5.1  41.2  335  10  5   6.1   3.3 |   6.9  44.4  270   4  2   9.2   5.1
  9250   5.5  41.9  345  10  5   6.3   3.4 |   7.6  45.7  250   3  2   9.1   5.0
  9000   5.9  42.6  345   9  5   6.4   3.5 |   8.2  46.8  240   3  2   9.1   5.0
  8750   6.4  43.5  350   9  5   7.0   3.9 |   8.9  48.0  235   3  1  10.5   5.7
  8500   6.9  44.4  355   9  5   8.5   4.7 |   9.7  49.5  225   3  1  11.1   6.1
  8250   7.5  45.5  355   9  5  10.0   5.5 |  10.5  50.9  220   2  1  10.4   5.7
  8000   8.2  46.8  360   9  5  10.1   5.6 |  11.3  52.3  215   2  1  10.3   5.6
  7750   8.9  48.0  360   9  4  11.3   6.2 |  12.0  53.6  210   2  1  10.7   5.9
  7500   9.7  49.5  005   8  4  10.1   5.6 |  12.9  55.2  205   2  1  12.3   6.8
  7250  10.3  50.5  005   7  4   7.4   4.1 |  13.8  56.8  200   2  1  13.2   7.2
  7000  10.9  51.6  005   7  3   9.6   5.3 |  14.8  58.6  195   2  1  12.6   6.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/10/2014 at 1500 MDT          |       09/10/2014 at 1800 MDT
                                           |
K index... +19.1  LI... -2.6               | K index... +23.2  LI... -1.1
CAPE... +254.0  CIN... -0.5                | CAPE... +61.3  CIN... -67.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.0 -85.0  255  65 34   2.8   1.5 | -65.7 -86.3  265  59 30   2.8   1.5
 45000 -59.6 -75.3  260  81 42   5.8   3.2 | -60.4 -76.7  265  69 36   5.2   2.9
 40000 -50.8 -59.4  260  73 37   6.5   3.6 | -52.4 -62.3  270  61 32   6.8   3.7
 38000 -46.9 -52.4  265  65 34   6.5   3.5 | -48.4 -55.1  275  57 29   6.7   3.7
 36000 -43.0 -45.4  265  58 30   6.5   3.5 | -44.4 -47.9  280  52 27   6.7   3.7
 34000 -39.6 -39.3  275  50 26   5.3   2.9 | -40.4 -40.7  285  49 25   6.5   3.6
 32000 -36.0 -32.8  285  44 22   5.4   2.9 | -36.0 -32.8  295  47 24   6.5   3.6
 30000 -32.0 -25.6  295  40 20   7.2   3.9 | -31.7 -25.1  300  45 23   7.6   4.2
 29000 -29.9 -21.8  300  38 20   7.2   3.9 | -29.4 -20.9  300  43 22   7.6   4.2
 28000 -27.7 -17.9  305  37 19   7.2   3.9 | -27.1 -16.8  300  42 22   7.4   4.1
 27000 -25.6 -14.1  310  34 18   7.0   3.8 | -25.1 -13.2  300  40 21   6.6   3.6
 26000 -23.5 -10.3  315  32 16   7.0   3.8 | -23.1  -9.6  305  38 19   6.6   3.6
 25000 -21.4  -6.5  320  30 15   7.0   3.8 | -21.2  -6.2  305  36 18   6.5   3.6
 24000 -19.5  -3.1  325  28 14   6.2   3.4 | -19.0  -2.2  305  33 17   7.7   4.2
 23000 -17.6   0.3  320  26 13   6.2   3.4 | -16.7   1.9  305  31 16   7.7   4.2
 22000 -15.8   3.6  315  24 12   6.2   3.4 | -14.3   6.3  305  29 15   8.0   4.4
 21000 -14.1   6.6  310  24 12   5.2   2.9 | -12.6   9.3  305  28 15   4.7   2.6
 20000 -12.6   9.3  305  25 13   5.2   2.9 | -11.2  11.8  305  29 15   4.7   2.6
 19500 -11.8  10.8  305  26 13   5.2   2.9 | -10.5  13.1  300  29 15   4.7   2.6
 19000 -11.0  12.2  305  26 13   5.2   2.8 |  -9.8  14.4  300  29 15   4.4   2.4
 18500 -10.3  13.5  305  28 14   5.0   2.7 |  -9.2  15.4  295  29 15   4.1   2.3
 18000  -9.6  14.7  305  29 15   5.0   2.7 |  -8.6  16.5  295  30 16   4.0   2.2
 17500  -8.8  16.2  300  31 16   6.3   3.4 |  -7.9  17.8  290  31 16   7.8   4.3
 17000  -7.9  17.8  300  32 16   6.4   3.5 |  -6.8  19.8  285  31 16   7.9   4.3
 16500  -7.0  19.4  295  33 17   7.2   4.0 |  -5.8  21.6  280  31 16   8.7   4.8
 16000  -5.9  21.4  295  31 16   8.1   4.4 |  -4.5  23.9  280  28 15   9.0   5.0
 15500  -4.2  24.4  295  27 14   8.2   4.5 |  -2.6  27.3  280  25 13   8.9   4.9
 15000  -3.1  26.4  295  25 13   8.3   4.5 |  -1.4  29.5  275  22 11   8.7   4.8
 14500  -1.9  28.6  295  22 11   7.8   4.3 |  -0.1  31.8  275  19 10   7.9   4.3
 14000  -0.9  30.4  295  18  9   7.1   3.9 |   0.9  33.6  270  17  9   6.8   3.7
 13500   0.1  32.2  300  14  7   7.0   3.8 |   1.9  35.4  265  15  8   7.0   3.8
 13000   1.1  34.0  305  10  5   6.7   3.7 |   3.0  37.4  255  13  7   8.0   4.4
 12500   2.0  35.6  315   6  3   6.3   3.5 |   4.2  39.6  245  12  6   7.0   3.8
 12000   3.0  37.4  320   3  2   7.3   4.0 |   5.1  41.2  235  11  6   6.7   3.7
 11750   3.5  38.3  320   2  1   7.2   3.9 |   5.6  42.1  230  11  6   6.6   3.6
 11500   4.0  39.2  000   0  0   6.9   3.8 |   6.1  43.0  225  11  6   6.7   3.7
 11250   4.4  39.9  165   1  1   7.3   4.0 |   6.6  43.9  220  11  6   5.7   3.1
 11000   5.0  41.0  165   2  1   9.0   4.9 |   6.9  44.4  210  11  5   4.9   2.7
 10750   5.7  42.3  160   3  2   9.6   5.3 |   7.3  45.1  205  11  6   5.1   2.8
 10500   6.4  43.5  160   4  2   9.5   5.2 |   7.6  45.7  200  11  6   5.1   2.8
 10250   7.0  44.6  160   5  3   7.9   4.3 |   8.0  46.4  195  12  6   4.8   2.6
 10000   7.6  45.7  160   5  3   8.7   4.8 |   8.4  47.1  190  12  6   6.1   3.3
  9750   8.3  46.9  160   5  3  10.9   6.0 |   8.9  48.0  185  13  7   7.5   4.1
  9500   9.1  48.4  160   6  3  10.4   5.7 |   9.4  48.9  185  14  7   7.4   4.0
  9250   9.9  49.8  160   6  3   9.5   5.2 |   9.9  49.8  180  14  7   7.7   4.2
  9000  10.5  50.9  160   6  3   9.1   5.0 |  10.5  50.9  180  15  8   8.1   4.4
  8750  11.3  52.3  165   6  3  10.5   5.8 |  11.1  52.0  180  15  8   9.7   5.3
  8500  12.1  53.8  160   6  3  11.1   6.1 |  11.8  53.2  180  15  8  10.5   5.8
  8250  12.9  55.2  160   7  3  10.5   5.8 |  12.6  54.7  180  15  8   9.7   5.3
  8000  13.7  56.7  160   7  4  10.6   5.8 |  13.3  55.9  180  15  8   9.7   5.3
  7750  14.5  58.1  160   7  4  10.2   5.6 |  14.0  57.2  180  15  7   9.5   5.2
  7500  15.2  59.4  160   7  4  11.7   6.4 |  14.7  58.5  175  14  7   8.6   4.7
  7250  16.2  61.2  160   7  4  13.7   7.5 |  15.3  59.5  175  14  7   8.0   4.4
  7000  17.2  63.0  160   7  4  12.4   6.8 |  15.9  60.6  175  13  7   8.3   4.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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